1. Field of the Invention
The present invention relates to a signal processing apparatus, and more particularly to a signal processing apparatus having a plurality of processing means for performing a plurality of functions.
2. Related Background Art
In present digital satellite TV broadcasting using communication satellites, electric program guide (EPG) data is transmitted together with video data and the like for subscriber services. Also in future digital satellite TV broadcasting using broadcast satellites or in ground wave digital TV broadcasting, similar services are expected (hereinafter, digital satellite TV broadcasting and ground wave digital TV broadcasting are collectively called “digital TV broadcasting”).
A TV receiver received EPG data displays the program information on its display unit or on an external display apparatus. A user selects a desired program from the displayed program information to automatically switch between programs or reserve a program or record a program in a recording unit connected to the TV receiver.
Digital TV broadcasting can broadcast several hundreds of channels. It is difficult for a user to find a desired program from such a very large number of programs. If EPG data is searched in accordance with the search conditions set by a user or if desired programs are registered as preferred programs, the user can find the desired program easily.
In analog TV-broadcasting, compressed reservation codes are used in practice in order to facilitate a program reservation. With this method, a program can be reserved only by entering a specific code from a remote controller, the specific code being written in each program frame of a TV program column of a newspaper, a magazine or the like. This reservation code contains compressed information such as a program date and time, a broadcasting time, and a channel. A program reservation can be made by entering a number having several digits.
For the program selection, program reservation, program search and the like by using an EPG screen, however, it is necessary to perform a complicated user operation such as a screen change, a screen scroll and the like by using a cursor key, an enter key and the like.
If an EPG screen, a program reservation setting screen or the like occupies a large area of the display, a user is disturbed by this screen to listen and view the program. If while one user listens or views a program, another user wants to display such screen, the user listening or viewing the program is disturbed.
With the program reservation method using a reservation code, the number of digits of each reservation code is large. Specifically, if a program has a broadcast start and end time such as 6:02 to 6:58, the number of digits increases and the input work is not easy.